Supplied By www.heating spares.co Tel. 0161 620 6677
19
installation
Fitting the Twin Pipe (Ø80 / 80)
Note: See table for maximum and minimum flue runs.
Where it is not possible to terminate the flue within the distance
permitted for coaxial flues, the twin flue pipe can be used by
fitting a special adaptor to the flue connector and using the aper-
ture for the air intake located on top of the combustion chamber.
Always ensure that the flue is adequately supported, using one
flue bracket per extension and avoiding low points. (MTS supply
suitable clamps as Part No. 705778).
To utilise the air intake it is necessary to:
1) Take the air intake cover off the top of the appliance
) Assemble the flange on the header supplied with the boiler
3) Insert the header on the tube or the elbow up until the lower
stop (you do not have to use the washer).
4) Insert the elbow/header in the boiler air intake hole and fasten
it with screws.
The twin flue pipes can be fitted with or without additional
elbows and need no clamps, simply ensure that the red o-ring is
inserted in the female end of the flue pipe and push the exten-
sion piece fully into the previous section of flue pipe or elbow,
check that the o-ring is not dislodged when assembling the flue
(greasing the seal will aid assembly).
Twin pipe can also be converted back to Coaxial flue to enable
vertical termination with a coaxial kit by using the pipe bridge
(Twin - Coaxial Adaptor - Part No. 3318089). When running the
twin flue pipe vertically.
It is not possible to terminate concentrically horizontally. Termi-
nation is only possible with separate air and exhaust terminals.
When siting the twin flue pipe, the air intake and exhaust
terminals must terminate on the same wall, the centres of the
terminals must be a minimum of 80 mm apart and the air intake
must not be sited above the exhaust terminal (refer to Fig. 10).
The air intake pipe can be run horizontally, however, the terminal
and the final 1 metre of flue must be installed either horizontally
or with a slight fall away from the boiler to avoid rain ingress.
It is also strongly recommended that the air intake pipe run be
constructed of insulated pipe to prevent condense forming on
the outside of the tube.
The maximum permissible flue length for twin flue is dependent
on the type of run used (see table on page 1).
For further information relating to flue runs not illustrated, please
contact the Technical Department on 0870 41 8180.
